Reactive polyorganosiloxane having nitrogen-containing heterocyclic group

Abstract

Provided is a reactive polyorganosiloxane having a nitrogen-containing heterocyclic group represented by formula 1. (R is a group selected from an alkyl group, an aryl group, and an aralkyl group; Ra is a group selected from an alkenyl group, an alkoxy group, a hydroxyl group, an amino group, and a monovalent organic group containing one or more hydroxyl groups or amino groups; X1 is a monovalent organic group containing a nitrogen-containing heterocycle having two or more nitrogen atoms; a is a number from 0 to 2,000; and b is a number from 1 to 30.)

Description

Reactive polyorganosiloxanes having nitrogen-containing heterocyclic groups

[0001] The present invention relates to a reactive polyorganosiloxane having a nitrogen-containing heterocyclic group.

[0002] Polyorganosiloxanes having reactive groups at both ends are generally suitable for introducing siloxane structures into various resins, and are used in a wide range of applications, including polyimide resins, epoxy resins, acrylic resins, urethane resins, and urea resins (see Patent Document 1). However, the resins containing polyorganosiloxanes may exhibit reduced adhesion to substrates. Furthermore, polyorganosiloxanes having unsaturated bonds at both ends are used as raw materials for addition-curable silicone resin compositions, but silicone resin compositions may be required to have improved flame retardancy.

[0003] On the other hand, compounds having heterocyclic rings exhibit good adhesion to metals and the like, and are therefore used as adhesion improvers and rust inhibitors. They are also known to be useful in imparting flame retardancy to silicone resin compositions (Patent Document 2). However, when a compound having a heterocyclic group is added alone to a resin composition, it may not be compatible with the resin or may produce uneven effects.

[0004] For these reasons, there has been a demand for the development of polyorganosiloxanes having reactive functional groups and organic groups containing heterocycles.

[0005] JP 2019-172894 A JP 2004-182758 A

[0006] The present invention has been made in view of the above circumstances, and aims to provide a polyorganosiloxane that can be expected to provide stable improvements in adhesion and flame retardancy when a resin containing a siloxane chain is formed in the structure.

[0007] As a result of intensive research to solve the above problems, the present inventors have found that a polyorganosiloxane having a nitrogen-containing heterocycle in a side chain and reactive groups at both ends can solve the above problems, and have completed the present invention.

[0008] That is, the present invention provides: 1. a reactive polyorganosiloxane having a nitrogen-containing heterocyclic group represented by the following formula (1): (In formula (1), each R is independently a group selected from an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, and an aralkyl group having 7 to 10 carbon atoms; R a are each independently a group selected from an alkenyl group having 2 to 12 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, a hydroxyl group, an amino group, and a monovalent organic group having 1 to 10 carbon atoms and containing one or more hydroxyl groups or amino groups; X 1 is a monovalent organic group containing a nitrogen-containing heterocycle having two or more nitrogen atoms, a is a number from 0 to 2,000, and b is a number from 1 to 30. The bonding order of the siloxane units bounded by a and b may be block or random. 2. X in the above formula (1) 1 3. The reactive polyorganosiloxane according to 1, wherein the nitrogen-containing heterocycle in the formula (1) is an imidazole ring. a is any one selected from alkenyl groups having 2 to 8 carbon atoms, hydroxyl groups, methoxy groups, ethoxy groups, 3-(2-hydroxyethoxy)propyl groups, 3-aminopropyl groups, and N-(2-aminoethyl)-3-aminopropyl groups; 3. The reactive polyorganosiloxane according to any one of 1 to 3, wherein all of the R in formula (1) are methyl groups.

[0009] According to the present invention, when various resins containing siloxane chains are formed in the structure, stable improvements in adhesion and flame retardancy can be expected. It is possible to provide a reactive polyorganosiloxane having a nitrogen-containing heterocyclic group in the side chain.

[0010] The polyorganosiloxane synthesized in Example 1 has imidazole groups on the side chains and amino groups on both ends. 1 1 is a H-NMR spectrum chart of the polyorganosiloxane having imidazole groups in the side chains and vinyl groups at both ends, synthesized in Example 2. 1 1 is a H-NMR spectrum chart.

[0011] The present invention will be described in more detail below. The reactive polyorganosiloxane having a nitrogen-containing heterocyclic group in the side chain of the present invention is represented by the following formula (1).

[0012]

[0013] In the above formula (1), each R is independently a group selected from an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, and an aralkyl group having 7 to 10 carbon atoms. The alkyl group having 1 to 10 carbon atoms represented by R may be linear, branched, or cyclic, and preferably has 1 to 8 carbon atoms, more preferably 1 to 6 carbon atoms. Specific examples thereof include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a cyclohexyl group, an octyl group, and a decyl group. The aryl group having 6 to 10 carbon atoms preferably has 6 to 8 carbon atoms, and specific examples thereof include a phenyl group and a tolyl group. The aralkyl group having 7 to 10 carbon atoms preferably has 7 or 8 carbon atoms, and specific examples thereof include a benzyl group and a phenethyl group. Among these, R is preferably a methyl group, an ethyl group, a propyl group, a butyl group, or a phenyl group, more preferably a methyl group or a phenyl group, still more preferably a methyl group, and particularly preferably all of R are methyl groups.

[0014] In the above formula (1), R a are each independently a group selected from an alkenyl group having 2 to 12 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, a hydroxyl group, an amino group, or a monovalent organic group having 1 to 10 carbon atoms and containing one or more hydroxyl or amino groups. aThe alkenyl group having 2 to 12 carbon atoms preferably has 2 to 10 carbon atoms, more preferably 2 to 8 carbon atoms, and specific examples thereof include vinyl group, propenyl group, butenyl group, pentenyl group, hexenyl group, octenyl group, decenyl group, etc. The alkoxy group having 1 to 4 carbon atoms preferably has 1 to 3 carbon atoms, and specific examples thereof include methoxy group, ethoxy group, propoxy group, isopropoxy group, butoxy group, etc. The monovalent organic group having 1 to 10 carbon atoms and containing one or more hydroxyl groups or amino groups preferably has 1 to 8 carbon atoms, more preferably 1 to 6 carbon atoms, and specific examples thereof include a 3-hydroxypropyl group, a 4-hydroxybutyl group, a 6-hydroxyhexyl group, an 8-hydroxyoctyl group, a 10-hydroxydecyl group, a 3-(2-hydroxyethoxy)propyl group, a 3-glycerylpropyl group, a 3-aminopropyl group, a 4-aminobutyl group, a 6-aminohexyl group, an 8-aminooctyl group, and an N-(2-aminoethyl)-3-aminopropyl group. a Particularly preferred examples of the alkyl group include alkenyl groups having 2 to 8 carbon atoms, hydroxyl groups, methoxy groups, ethoxy groups, 3-(2-hydroxyethoxy)propyl groups, 3-aminopropyl groups, and N-(2-aminoethyl)-3-aminopropyl groups.

[0015] In the above formula (1), X 1 is a monovalent organic group containing a nitrogen-containing heterocycle having two or more nitrogen atoms. Specific examples of heterocyclic groups having two or more nitrogen atoms include imidazole groups, imidazoline groups, pyrazole groups, pyrazoline groups, triazole groups, tetrazole groups, indazole groups, benzimidazole groups, azaindole groups, azaindazole groups, purine groups, and benzotriazole groups. Among these, imidazole groups, triazole groups, benzimidazole groups, and benzotriazole groups are preferred, imidazole groups and benzotriazole groups are more preferred, and imidazole groups are even more preferred. Some or all of the hydrogen atoms in these groups may be substituted with alkyl groups such as methyl groups. These nitrogen-containing heterocyclic groups are bonded to silicon atoms via linking groups, and X 1is preferably composed of these nitrogen-containing heterocyclic groups and a linking group. Examples of the linking group that bonds the nitrogen-containing heterocyclic group to the silicon atom include divalent organic groups having 2 to 10 carbon atoms. Such divalent organic groups are preferably divalent hydrocarbon groups having 2 to 10 carbon atoms. More preferably, they are alkylene groups having 2 to 8 carbon atoms. The alkylene groups having 2 to 8 carbon atoms may be either linear or branched, and specific examples thereof include ethylene, 1,2-propylene (methylethylene), trimethylene, tetramethylene, pentamethylene, hexamethylene, heptamethylene, and octamethylene groups. Of these, 1,2-propylene (methylethylene) and trimethylene groups are preferred, and trimethylene is more preferred. X 1 Specific examples of the monovalent organic group containing a nitrogen-containing heterocycle having two or more nitrogen atoms include, but are not limited to, the following:

[0016] (In the formula, the wavy line indicates the bond to the silicon atom.)

[0017] In the above formula (1), a is a number from 0 to 2,000, preferably a number from 1 to 1,000, and more preferably a number from 3 to 500. In the above formula (1), b is a number from 1 to 30, preferably a number from 1 to 20, and more preferably a number from 1 to 15. Regarding a and b, when a is 0, b is preferably 1, and when a is greater than 0, a and b are preferably numbers that satisfy 3≦a / b≦300, and more preferably numbers that satisfy 3≦a / b≦100. The bonding order of the siloxane units bracketed by a and b may be block or random. The values ​​of a and b in the above formula (1) are determined based on the values ​​described in the examples below. 1 It can be determined by H-NMR.

[0018] Specific examples of the polyorganosiloxane represented by formula (1) include, but are not limited to, the following:

[0019]

[0020]

[0021]

[0022]

[0023] In the above formula, a1 is a number from 0 to 2,000, and b1 is a number from 1 to 30.

[0024] The method for producing the reactive polyorganosiloxane having a nitrogen-containing heterocyclic group of the present invention is not particularly limited. For example, the polyorganosiloxane of the present invention can be produced by an equilibration reaction between a cyclic organosiloxane compound represented by the following formula (2), an organosiloxane compound represented by the following formula (3), and, if necessary, a cyclic organosiloxane compound represented by the following formula (4) in the presence of an acidic or basic catalyst, preferably a basic catalyst.

[0025] (In the formula, R, R a , X 1 is the same as above. m is a number from 1 to 5, n is a number from 0 to 10, p is a number from 0 to 200, and q is a number from 3 to 10.

[0026] Specific examples of the cyclic organosiloxane compound represented by the above formula (2) include, but are not limited to, the following: (In the formula, m and n are the same as above.)

[0027] Specific examples of the organosiloxane compound represented by the above formula (3) include polydimethylsiloxane capped at both ends with aminopropyl groups, polydimethylsiloxane capped at both ends with vinyl groups, polydimethylsiloxane capped at both ends with silanol groups, polydimethylsiloxane capped at both ends with methoxy groups, polydimethylsiloxane capped at both ends with ethoxy groups, polydimethylsiloxane capped at both ends with 3-(2-hydroxyethoxy)propyl groups, and polydimethylsiloxane capped at both ends with N-(2-aminoethyl)-3-aminopropyl groups.

[0028] Specific examples of the cyclic organosiloxane compound represented by the above formula (4) include hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane, dodecamethylcyclohexasiloxane, hexaethylcyclotrisiloxane, octaethylcyclotetrasiloxane, hexaphenylcyclotrisiloxane, and octaphenylcyclotetrasiloxane.

[0029] The amounts (ratios) of the cyclic organosiloxane compound represented by the formula (2), the organosiloxane compound represented by the formula (3), and the cyclic organosiloxane compound represented by the formula (4) used as needed can be selected arbitrarily depending on the degree of polymerization (or the number of silicon atoms) of the reactive polyorganosiloxane having a nitrogen-containing heterocyclic group represented by the formula (1).

[0030] The reaction conditions are not particularly limited, and may be, for example, 10 to 200° C. and 1 to 24 hours. The reaction can be carried out without using a solvent, or, if necessary, may be carried out using a solvent such as toluene or xylene, as long as it does not inhibit the reaction.

[0031] Specific examples of acidic catalysts include sulfuric acid, trifluoromethanesulfonic acid, etc., and specific examples of basic catalysts include potassium hydroxide, sodium hydroxide, potassium siliconate, sodium siliconate, etc. Although the use of these catalysts allows the equilibration reaction to proceed stably, in the present invention, basic catalysts are preferred, and potassium siliconate is more preferred.

[0032] Generally, when an acidic catalyst such as sulfuric acid or trifluoromethanesulfonic acid is used as the catalyst, the equilibration reaction is carried out at a relatively low temperature, for example, from 10 to 150°C, preferably from 20 to 100°C, for 30 minutes to 12 hours, preferably from 1 to 8 hours, and the acidic catalyst is used in an amount of 100 to 10,000 ppm, preferably 300 to 5,000 ppm by mass, based on the total amount of organosiloxane compounds used as raw materials.

[0033] On the other hand, when a basic catalyst such as potassium hydroxide, sodium hydroxide, potassium siliconate, or sodium siliconate is used as the catalyst, the equilibration reaction is carried out at a relatively high temperature, for example, 50 to 180°C, preferably 80 to 160°C, for 1 to 24 hours, preferably 2 to 12 hours, and the basic catalyst is used in an amount of 1 to 1,000 ppm, preferably 10 to 500 ppm by mass, in terms of hydroxide, based on the total mass of the organosiloxane compounds used as raw materials.

[0034] After the reaction is complete, the catalyst is neutralized and, if necessary, filtration is carried out, and the filtrate is then purified by distillation or the like under atmospheric pressure or reduced pressure to obtain the desired polyorganosiloxane.

[0035] The reactive polyorganosiloxane having a nitrogen-containing heterocyclic group of the present invention can be introduced into various resins such as polyimide resins, epoxy resins, acrylic resins, urethane resins, and urea resins, and can therefore be suitably used for resin modification applications. A composition containing a resin modified by introducing the polyorganosiloxane of the present invention cures and exhibits good adhesion to the substrate, and also exhibits good flame retardancy. In particular, a composition containing a polyimide resin modified by introducing the polyorganosiloxane of the present invention can provide a cured product with good adhesion. Furthermore, a composition containing a silicone resin obtained from the polyorganosiloxane of the present invention can provide a cured product with improved flame retardancy.

[0036] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to the following examples. 1 H-NMR was measured using an AVANCE-III 400 MHz (manufactured by BRUKER) and deuterated chloroform as a solvent.

[0037] [Example 1] A separable flask equipped with a thermometer, a stirrer, and a reflux condenser was charged with 54 g of a cyclic polyorganosiloxane represented by the following formula (a), 129 g of a polyorganosiloxane having amino groups at both ends represented by the following formula (b), and 0.17 g of 3 mass% potassium siliconate, and heated and stirred at 155 ° C. for 3 hours. Thereafter, 0.023 g of ethylene chlorohydrin was added, and the mixture was heated and stirred at 155 ° C. for an additional 1 hour to terminate the polymerization, and low molecular weight components were distilled off under reduced pressure at 115 ° C. / 600 Pa to obtain 159 g of a polyorganosiloxane having imidazole groups on the side chains represented by the following formula (c) and having amino groups at both ends. The polyorganosiloxane represented by the following formula (c) obtained in FIG. 1 The H-NMR spectrum is shown.

[0038] 1 H-NMR (400MHz, CDCl3): δ-0.15 to 0.25 (m, 63H), 0.38 to 0.58 (m, 6H), 1.20 to 1.48 (m, 4H), 1.70 to 1.84 (m, 2H), 2.52-2.77 (m, 4H), 3.77-3.94 (m, 2H), 6.82-6.89 (s, 1H), 7.00-7.04 (s, 1H), 7.39-7.46 (s, 1H)

[0039]

[0040] [Example 2] 45 g of polyorganosiloxane represented by the above formula (a), 7.2 g of 1,3-divinyl-1,1,3,3-tetramethyldisiloxane, 126 g of 2,2,4,4,6,6,8,8-octamethylcyclotetrasiloxane, and 0.17 g of 3 mass% potassium siliconate were charged and heated and stirred at 155 ° C. for 3 hours. Thereafter, 0.022 g of ethylene chlorohydrin was added, and the mixture was heated and stirred at 155 ° C. for an additional 1 hour to terminate the polymerization, and low molecular weight components were distilled off under reduced pressure at 115 ° C. / 600 Pa to obtain 151 g of polyorganosiloxane having imidazole groups on the side chains represented by the following formula (d) and vinyl groups at both ends. The polyorganosiloxane represented by the following formula (d) obtained in FIG. 1 The H-NMR spectrum is shown.

[0041] 1 ​​H-NMR (400MHz, CDCl3): δ-0.14 to 0.24 (m, 374H), 0.37 to 0.50 (m, 8H), 1.69 to 1.86 (m, 8H), 3.80 to 3.93 (m, 8H), 5.6 7-5.75 (m, 2H), 5.88-5.94 (m, 2H), 6.04-6.15 (m, 2H), 6.84-6.88 (s, 4H), 7.01-7.05 (s, 4H), 7.41-7.46 (s, 4H)

[0042]

[0043] [Example 3] In Example 2, 24 g of the polyorganosiloxane represented by the above formula (a), 0.97 g of 1,3-divinyl-1,1,3,3-tetramethyldisiloxane, 151 g of 2,2,4,4,6,6,8,8-octamethylcyclotetrasiloxane, and 0.16 g of 3 mass% potassium siliconate were used. In the same manner as in Example 2, except that the reaction was started using 24 g of the polyorganosiloxane represented by the following formula (e) having imidazole groups on the side chain and vinyl groups at both ends, 141 g was obtained.

[0044] 1 H-NMR (400MHz, CDCl3): δ-0.29 to 0.32 (m, 3054H), 0.36 to 0.53 (m, 30H), 1.69 to 1.90 (m, 30H), 3.80 to 4.01 (m, 30H), 5.6 3-5.77 (m, 2H), 5.85-5.97 (m, 2H), 6.03-6.18 (m, 2H), 6.84-6.96 (s, 15H), 7.02-7.13 (s, 15H), 7.49-7.65 (s, 15H)

[0045]

[0046] ​[Example 4] 14 g of polyorganosiloxane represented by the above formula (a), 13 g of polyorganosiloxane having hydroxyl groups at both ends represented by the following formula (f), 153 g of 2,2,4,4,6,6,8,8-octamethylcyclotetrasiloxane, and 0.17 g of 3% by mass potassium siliconate were charged and heated and stirred for 3 hours at 155 ° C. Thereafter, 0.022 g of ethylene chlorohydrin was added, and the mixture was heated and stirred for another 1 hour at 155 ° C. to terminate the polymerization, and the low molecular weight components were distilled off under reduced pressure at 115 ° C. / 600 Pa to obtain 153 g of polyorganosiloxane having imidazole groups on the side chains represented by the following formula (g) and hydroxyl groups at both ends.

[0047] 1 H-NMR (400MHz, CDCl3): δ-0.26 to 0.33 (m, 706H), 0.40 to 0.54 (m, 4H), 1.71 to 1.94 (m, 4H), 2.82 ~3.32 (br, 2H), 3.82 ~ 4.08 (m, 4H), 6.84 ~ 6.97 (s, 2H), 7.05 ~ 7.16 (s, 2H), 7.54 ~ 7.68 (s, 2H)

[0048]

[0049] [Example 5] 9 g of polyorganosiloxane represented by the above formula (a), 9 g of polyorganosiloxane having ethoxy groups at both ends represented by the following formula (h), 160 g of 2,2,4,4,6,6,8,8-octamethylcyclotetrasiloxane, and 0.17 g of 3% by mass potassium siliconate were charged and heated and stirred for 3 hours at 155 ° C. Thereafter, 0.022 g of ethylene chlorohydrin was added, and the mixture was heated and stirred for another 1 hour at 155 ° C. to terminate the polymerization, and the low molecular weight components were distilled off under reduced pressure at 115 ° C. / 600 Pa to obtain 152 g of polyorganosiloxane having imidazole groups in the side chains represented by the following formula (i) and ethoxy groups at both ends.

[0050] 1 ​​H-NMR(400MHz,CDCl3):δ-0.28~0.34(m,1100H)、0.439~0.52(m,4H)、1.08~1.29(m,6H)、1.70~1.92(m,4H)、3.62~4.09(m,8H)、6.82~6.97(s,2H)、7.04~7.15(s,2H)、7.52~7.65(s,2H)

[0051]

Claims

1. A reactive polyorganosiloxane having a nitrogen-containing heterocyclic group represented by the following formula (1): (In formula (1), each R is independently a group selected from an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, and an aralkyl group having 7 to 10 carbon atoms; R a are each independently a group selected from an alkenyl group having 2 to 12 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, a hydroxyl group, an amino group, and a monovalent organic group having 1 to 10 carbon atoms and containing one or more hydroxyl groups or amino groups; X 1 is a monovalent organic group containing a nitrogen-containing heterocycle having two or more nitrogen atoms, a is a number from 0 to 2,000, and b is a number from 1 to 30. The bonding order of the siloxane units bounded by a and b may be block or random.

2. X in the formula (1) 1 2. The reactive polyorganosiloxane according to claim 1, wherein the nitrogen-containing heterocycle in the formula (I) is an imidazole ring.

3. R ​​in the formula (1) a is any one selected from an alkenyl group having 2 to 8 carbon atoms, a hydroxyl group, a methoxy group, an ethoxy group, a 3-(2-hydroxyethoxy)propyl group, a 3-aminopropyl group, and an N-(2-aminoethyl)-3-aminopropyl group. The reactive polyorganosiloxane according to claim 1 or 2.

4. The reactive polyorganosiloxane according to any one of claims 1 to 3, wherein all R's in formula (1) are methyl groups.

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